<!DOCTYPE html>
<html lang='en'>
<head>
    <meta charset='UTF-8'>
    <meta name='viewport' content='width=device-width, initial-scale=1.0'>
    <meta http-equiv='X-UA-Compatible' content='ie=edge'>
    <title>Document</title>
</head>
<body>
    <div id='app'>
        {{bigStr}}
    </div>
    <script src='https://cdn.jsdelivr.net/npm/vue@2.6.10/dist/vue.js'></script>
    <script>
        new Vue({
            el: '#app',
            data:{ 
                str:"english"
             },
            methods:{},
            directive:{},
            // 计算属性
            computed:{
                // 形式上是函数 最终使用的时候当做属性来使用
                bigStr(){
                    return this.str.toUpperCase()
                }
            }
        })
    </script>
</body>
</html>